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The asymmetric growth of Cu 6 Sn 5 intermetallic compound (IMC) in a Cu/Sn/Cu interconnection system was studied during the transient liquid phase (TLP) soldering process with the assistance of the vertical ultrasonic vibration. Being different from the symmetrical growth during isothermal aging without ultrasonic waves (USW), highly asymmetrical growth of Cu 6 Sn 5 at the upper and down Sn/Cu interfaces was observed with the vertical USW, i.e., Cu 6 Sn 5 grains exhibited scallop-type morphology, and were discrete at the upper Sn/Cu interface (the side of ultrasonic action); while that at the lower Sn/Cu interface (the opposite side of ultrasonic action) exhibited column-type morphology, and were conterminous. Under the assistance of USW, the Cu 6 Sn 5 grains were remarkably refined, the shear strength of joint was increased, and the fracture mode was changed from transgranular fracture to transgranular and intergranular fracture. This anomalous behavior can be completely ascribed to the asymmetrical ultrasonic effects across the entire Sn the intermediate layer of Sn. [Display omitted] • The abnormal asymmetric growth of Cu 6 Sn 5 was first observed and investigated. • Ultrasonic waves create uneven growth of Cu 6 Sn 5 compound on different substrates. • Ultrasonic waves create different grain morphology in Cu 6 Sn 5 on different substrates. • The USW-formed joint exhibited both transgranular and intergranular fracture. [ABSTRACT FROM AUTHOR]

We propose herein an algorithm to resample the Raman spectra which aims to correct the predicted error induced by spectral shift. The same set of training data for both human and nonhuman blood Raman spectra was applied to build the model using partial least squares (PLS) method. Several kinds of Raman spectra of the blood samples originating from human, goose, monkey, chicken, sheep and duck without spectral shift were used to validate the model. The Raman spectra of the same blood samples with a shift of 9.18 cm-1 were used to illustrate the influence of the spectral shift to the model. To demonstrate the effectiveness of the algorithm proposed, Raman spectra with spectral shift were resampled. The results show that the resampling algorithm can improve both the stability and accuracy of the model and reduce the impact of the spectral shift, which is promising for quantitative or qualitative analysis in Raman spectroscopy for complex samples. [ABSTRACT FROM AUTHOR]

The effect of substrate temperature (TS) on the behavior of field emission, microstructure, optical band gap, and the surface energy of N-doped SrTiO3 thin films coated on silicon tip arrays has been examined in detail. Results indicate that the TS dominates the chemical states of nitrogen added to the sputtered SrTiO3 films and hence the observations. At the critical temperature of 600 °C, nitrogen atoms incorporate into the oxide film with sp-hybridization features. The generation of the nonbonding lone pair states narrows the optical band gap and the lone pair induced antibonding dipoles lower the threshold field for electron emission substantially. At lowered TS, molecular adsorption of nitrogen dominates. Contact angle measurements further evidence for the presence of antibonding dipole states at the surfaces which is responsible for the adsorbate-induced surface stress. [ABSTRACT FROM AUTHOR]

The effect of nitrogen (N) doping on the behavior of field emission, surface energy and the band structure of strontium titanate (SrTiO3) thin films coated on silicon tip arrays has been examined in detail. Measurements using x-ray photoelectron spectroscopy, ellipsometry, water contact angle and field emission testing revealed that the optimal 50%-nitrogen partial pressure (PN) could improve substantially the threshold field of electron emission of the SrTiO3 films accompanied with narrowed band gap, lowered surface energy and work function and a negative energy shift of the N 1s level from 404 to 396 eV. Results evidence consistently the presence of the nonbonding lone pairs and the lone pair induced antibonding dipoles upon tetrahedron formation which is responsible for the observations. At PN below and above the optimal value physisorption and hydrogen bond likes formation like to occur. [ABSTRACT FROM AUTHOR]

Abstract A graphene nanosheets reinforced Ag-Cu composite filler (Ag-Cu + GNSs) was developed by introducing GNSs into Ag-Cu powder filler. Unidirectional carbon fiber reinforced lithium aluminosilicate matrix composites (UD-C f /LAS composites) and Ti–6Al–4V alloy were brazed with Ag-Cu + GNSs composite filler. The typical interfacial microstructure of joint was Ti–6Al–4V/Ti(s,s)/Ti 2 Cu/TiCu/Ag(s,s)/Ti 3 Cu 4 /Cu(s,s)+TiCu + TiC/Ti 3 Cu 4 /TiC + TiSi 2 /UD-C f /LAS composites. The in situ synthesized TiCu + TiC composite from the reaction between Ti and GNSs had the following benefits: 1) refined the microstructure of the joint; 2) reinforced the joint; 3) alleviated the thermal stress of the joint by constraining the growth of continuous Ti 3 Cu 4 intermetallic layers. Moreover, with the increase of GNSs content, the amount of TiCu + TiC phases increased. Ag(s,s) and Ti 3 Cu 4 became uniform and fine in the interlayer. Both the thickness of reaction layers and the size of granular Ti 3 Cu 4 and TiCu + TiC phases firstly increased and then decreased with the rise of the brazing temperature. On the contrary, the content of Ag based composite decreased at first and then increased. The highest shear strength of joints reached 45.5 MPa with 0.5% GNSs addition when brazed at 900 °C for 10 min. Based on the experimental results, the interface evolution mechanism of the Ti–6Al–4V/Ag-Cu + GNSs/UD-C f /LAS composites joint was investigated. Highlights • TC4/C f /LAS composites joints were brazed by GNSs reinforced composite filler. • The determination of interface reaction phases was realized by TEM. • Brazing temperature and addition of GNSs had influence on the joints microstructure. • The highest shear strength of joints reached 45.5 MPa. • Microstructural evolution mechanism and reactions of brazed joints were expounded. [ABSTRACT FROM AUTHOR]

Abstract C/C composites were successfully brazed to Nb substrate using Cu75Pt25 filler metal. The typical interfacial microstructure of brazed joints was C/C composites/NbC/Nb(s, s)/Cu(s, s)/NbPt 2 /Nb 3 Pt/Nb(s, s)/Nb. The effect of brazing temperature on the interfacial microstructure and joints properties were investigated in details. With the increase of temperature, the Nb-Pt reaction layer thickened and the thickness of brazing seam declined. The thickness of Nb(s, s) layer at C/C composites side increased gradually with the increase of temperature and then declined when brazing temperature was over 1160 °C. The optimal average shear strength of 26.7 MPa at room temperature and highest shear strength of 17.6 MPa at 600 °C were obtained when the joints were brazed at 1160 °C for 20 min. Highlights • Vacuum brazing of C/C composites and Nb was achieved. • High temperature Cu75Pt25 brazing alloy was developed and introduced into brazing process. • Interfacial microstructure of brazed joint was characterized. • Interfacial microstructural morphology strongly depended on the brazing temperature. • The highest average shear strength of brazed joints reached 26.7 MPa. [ABSTRACT FROM AUTHOR]

Joining of graphite materials is problematic primarily due to the poor wettability of non-active filler metal on these materials. In an attempt to overcome this problem, magnetron sputtering deposition of Cr film on graphite was performed to modify the surface of the graphite. The wetting and brazing of graphite are carried out using non-active AgCu eutectic filler metals after deposition. The results indicated that surface modification enables wetting and joining of graphite with non-active filler. Cr film reacted with graphite forming Cr-C interfacial reaction layer, which resulted in the decrease of contact angle. Reliable graphite/graphite joints were obtained at temperature from 1113 K to 1233 K for 10 min. The typical interfacial microstructure of the brazed joint is graphite/Cr-C layer/Ag(s,s) + Cu(s,s) eutectic phase/Cr-C layer/graphite. The optimal shear strength of the joint was 13.6 MPa when the brazing parameters were 1173 K for 10 min. [ABSTRACT FROM AUTHOR]

The wettability of zirconia with Sn0.3Ag0.7Cu-Ti (SAC-Ti) alloys was investigated via the sessile drop method with the increase of temperature. Zirconia, pre-metallized with SAC-Ti metal powder at 900 °C, was brazed to copper using an SAC solder paste at the low temperature of 250 °C. The active element Ti reduced the contact angle as the temperature increased. The lowest contact angle of 8° was obtained with SAC-4 wt% Ti which possessed sufficient Ti and appropriate fluidity. When zirconia was pre-metallized with SAC-4 wt% Ti alloy, the typical microstructure of the copper/SAC/zirconia joint was copper/Cu 6 Sn 5 layer/β-Sn layer containing Ti 3 Sn and Ti 6 Sn 5 phases/Ti 3 Sn layer/TiO x layer/zirconia. As the Ti content increased, more Ti-Sn intermetallic compounds remained in the seam, and the shear strength increased first and thereafter decreased. The highest shear strength of 19.1 MPa was achieved as zirconia was pre-metallized with SAC-4 wt% Ti. Fracture analyses indicated that brittle fracture was initiated at the reaction layers adjacent to zirconia and propagated in the seam during shear test. [ABSTRACT FROM AUTHOR]

TZM alloy and ZrC particle reinforced W composite (ZrC p -W) were vacuum brazed using Ti-61Ni eutectic brazing alloy. The typical interfacial microstructure of the brazed joint consisted of three zones: a Mo solid solution layer, a brazing seam consisting of TiNi phase, TiNi 3 phase and (Ti, Zr)Ni 2 phase, and a diffusion layer composed of W particles, (Ti, Zr)C particles and (Ti, Zr)Ni 2 phase. The results revealed that brazing temperature affected the interfacial morphologies of the joint, the phase constituents of the brazing seam, the element contents of these phases and the mechanical properties of the brazed joint. The optimal shear strengths at room temperature and at 800 °C reached 124.8 MPa and 82.3 MP respectively when brazed at 1240 °C for 10 min. Meanwhile, the fracture paths located at the TZM substrate and the fracture surface exhibited inter-granular fracture characteristics. [ABSTRACT FROM AUTHOR]

Zirconia ceramic and titanium have been applied more and more extensively in biomedical fields. In this work, reliable brazed joints of ZrO 2 /Sn-3Ti/AuSn20/Ti were achieved by pre-metallized ZrO 2 using biocompatible Sn-3Ti foil. The interfacial microstructures and mechanical properties of the joints brazed at different brazing temperatures for different holding times were fully investigated. The typical interfacial microstructure of ZrO 2 /Sn-3Ti/AuSn20/Ti joint was ZrO 2 /Ti 2 O 3 + Ti 11.3 Sn 3 O 10 / β-Sn + Ti 6 Sn 5 + Ti 3 Sn + AuSn 2 + AuSn 4 + massive AuTi 5 Sn 3 /layered AuTi 5 Sn 3 /Ti. The brazing temperatures and holding times had great influences on the type, quantity and morphology of the intermetallic compounds (IMCs) in the joints. The main phase on the interface transformed from AuSn 2 to AuSn 4 and IMCs gradually agglomerated and grew up. Besides, the thickness of layered AuTi 5 Sn 3 increased. The optimal shear strength of ∼48.6 MPa was obtained at 550 °C for 30 min. The joint cracked at Ti 2 O 3 layer on the ZrO 2 side and extended along the AuSn 2 phase and the massive AuTi 5 Sn 3 phase. • Low temperature brazing of biomedical ZrO 2 /Ti was achieved by pre-metallized ZrO 2 using Sn-Ti foil. • The main phase in Zone II transformed from AuSn 2 to AuSn 4 and layered AuTi 5 Sn 3 thickened as the brazing parameters increased. • The thickness of layered AuTi 5 Sn 3 greatly affected the crack of the joints. • ftable The optimal shear strength of ∼48.6 MPa was obtained at 550 °C for 30 min. [ABSTRACT FROM AUTHOR]

Abstract: The influence of heat exposure during production of casein on its plasticizing effectiveness was investigated. A model self leveling underlayment (SLU) formulation was used to assess the dispersing power of casein. It was found that elevated temperature and long exposure times can induce chemical changes in the casein proteins which reduce their performance. Particularly, crosslinking accompanied by partial decomposition (denaturation) of the casein biopolymer as evidenced by fast protein liquid chromatography and gel permeation chromatography was found to be responsible for reduced dispersing power. As an optimum drying condition, a temperature of 110°C and a short exposure time of up to 2h are recommended. Under this condition, the wet casein rapidly releases its water while maintaining its full dispersion power. Understanding the temperature and exposure-time dependent behavior of casein proteins can help to produce more consistent casein qualities. [Copyright &y& Elsevier]

This study evaluated the efficacy of a brief integrative multiple behavior intervention and assessed risk factors as mediators of behavioral outcomes among older adolescents. A randomized controlled trial was conducted with participants randomly assigned to either a brief intervention or standard care control with 3-month follow-up. A total of 479 students attending two public high schools participated. Participants receiving the intervention showed a significant reduction in quantity × frequency of alcohol use, and increases in fruit and vegetable consumption and frequency of relaxation activities, compared to those receiving the control, P's = .01. No effects were found on cigarette and marijuana use, exercise and sleep. Effect sizes were small with alcohol use cessation effects reaching medium size. Intervention effects were mediated by changes in peer influenceability for alcohol use, and self-efficacy and self-image for health promoting behaviors. Findings suggest that the brief intervention resulted in health risk and promoting behavior improvements for adolescents, with outcomes mediated by several risk factors. [ABSTRACT FROM AUTHOR]

Abstract: A fast and accurate method of assessing the quality of casein superplasticizer is presented. The method is based on analysis of the content of α-, β- and κ-casein proteins contained in whole casein by ion exchange fast protein liquid chromatography (FPLC). The chromatographic profiles of six commercial casein samples were determined, revealing that the amount of κ-casein present in the biopolymer is the main assessment criteria for the quality of casein. For high dispersing effectiveness, the content of κ-casein needs to be high. The reason is that at pH ~12, a high content of κ-casein results in submicelles possessing smaller size (diameter ~10nm), as was proven by dynamic light scattering measurement (DLS). These smaller submicelles are supposed to adsorb on cement in higher amount than large submicelles. Using this FPLC method, the dispersing performance of any casein sample can be determined very quickly without physical testing of mortar. [Copyright &y& Elsevier]

Background. Basic fibroblast growth factor (bFGF) has shown potential in clinical practice to accelerate wound healing, but the underlying biomolecular mechanism remains largely unknown. Fibroblasts are the most important cells involved in producing and remodelling the extracellular matrix (ECM) in wound healing, and are one of the major target cells of bFGF in wound repair. To date, however, we have little idea of whether there is any specific relationship between bFGF and ECM metabolism. This study aimed to investigate whether bFGF improves wound repair by regulating the balance of ECM synthesis and degradation. Objective. To investigate the effects of bFGF on the expression of fibronectin, collagen and matrix metalloproteinase (MMP)-1 of human skin fibroblasts (HSFs) and to evaluate whether it contributes to improving the quality of wound healing. Methods. HSFs were stimulated with bFGF for 72 h, and then production of fibronectin, collagen and MMP-1 was detected, using reverse transcription PCR at the transcriptional level and Western blot analysis at post-transcriptional level. Results. bFGF stimulation resulted in increases in fibronectin expression of 1.31-, 1.47-, 1.57- and 1.62-fold in a dose-dependent manner in response to 10 ng/mL, 50 ng/mL, 100 ng/mL and 500 ng/mL of bFGF, respectively, but had no effect on the expression of collagen. Further investigation revealed that bFGF dose-dependently upregulated the expression of MMP-1. Conclusion. This study supports the hypothesis that bFGF has the potential to accelerate wound healing and improve the quality of wound healing by regulating the balance of ECM synthesis and degradation, suggesting a potential antiscarring role in wound healing. [ABSTRACT FROM AUTHOR]

Two approximations to convective transport have been implemented in an offline chemistry transport model (CTM) to explore the impact on calculated atmospheric CO2 distributions. Global CO2 in the year 2000 is simulated using the CTM driven by assimilated meteorological fields from the NASA's Goddard Earth Observation System Data Assimilation System, Version 4 (GEOS-4). The model simulates atmospheric CO2 by adopting the same CO2 emission inventory and dynamical modules as described in Kawa et al. (convective transport scheme denoted as Conv1). Conv1 approximates the convective transport by using the bulk convective mass fluxes to redistribute trace gases. The alternate approximation, Conv2, partitions fluxes into updraft and downdraft, as well as into entrainment and detrainment, and has potential to yield a more realistic simulation of vertical redistribution through deep convection. Replacing Conv1 by Conv2 results in an overestimate of CO2 over biospheric sink regions. The largest discrepancies result in a CO2 difference of about 7.8 ppm in the July NH boreal forest, which is about 30% of the CO2 seasonality for that area. These differences are compared to those produced by emission scenario variations constrained by the framework of Intergovernmental Panel on Climate Change (IPCC) to account for possible land use change and residual terrestrial CO2 sink. It is shown that the overestimated CO2 driven by Conv2 can be offset by introducing these supplemental emissions. [ABSTRACT FROM AUTHOR]

The mechanical properties and failure mechanisms of self-piercing riveted-adhesive joints of carbon fiber-reinforced polymers/6061-T6 aluminum plates was investigated. The effects of riveting pressure, aluminum surface treatment, and lap length on the mechanical properties of the joints were analyzed. The microscopic morphology of the joint at each stage of the failure process was obtained by tensile-shear test and electron microscopy scan, on which the changes of CFRP, aluminum plate, rivet, and adhesive layer at different stages were further discussed to reveal the failure mechanism of the joint. The results showed that the joint strength could be improved by appropriately increasing the riveting pressure. The surface treatment of aluminum plate could improve the surface properties of the joint, and the joint strength showed a trend of first increasing and then decreasing with the increase of the sandpaper mesh. Increasing the lap length led to an increase in joint strength; however, when the lap length was increased to a certain value, the increase in joint strength was not obvious. The failure process of the adhesive riveted specimen was from the failure of the adhesive layer to the failure of the rivet, and after rivet failure, the joint failed completely. [ABSTRACT FROM AUTHOR]

In this work, we synthesized a superhydrophobic self-healing silane hybrid coating based on benzotriazole (BTA) loaded hollow CeO 2 nano-capsules on copper substrate and evaluated the anti-corrosion and self-healing capability in 1 mol/L NaCl solution. The CeO 2 nano-carriers possessed a high loading capacity of 24.7% for the BTA inhibitor. The constructed CeO 2 @BTA/silane composite shifted the corrosion potential of copper substrate to more inert value. Both the anodic and cathodic reaction rates during copper corrosion process were remarkably inhibited. The corrosion current density was over three orders of magnitude smaller than that of the neat silane coating. Electrochemical impedance spectroscopy revealed that the protection efficiency was 99.5% and the polarization resistance was reduced slightly after 15 days of corrosion for the prepared CeO 2 @BTA/silane hybrid coating. The prepared coating also exhibited an excellent self-healing ability to external damages by fast desorption of the BTA inhibitor. [Display omitted] • Multifunctional silane coating based on benzotriazole loaded CeO2 nano-containers was successfully constructed. • The CeO2 nano-carriers possessed a high loading capacity of 24.7%. • The hybrid coating exhibited excellent short-term and long-term anti-corrosion performance. • The composite coating presented dual self-healing capability. [ABSTRACT FROM AUTHOR]

A superhydrophobic silane coating was modified by incorporating hollow CeO 2 nanocontainers loaded with 1,5-naphthalenediol (ND) and used for the corrosion protection of an AA2024-T3 aluminum alloy. The CeO 2 nanocontainers exhibited a high loading capacity of 22.1 % for the ND inhibitor. After 8 h immersion, 93 % of the ND inhibitor was desorbed from CeO 2 @ND nanoparticles in a 3.5 wt% NaCl solution. Electrochemical impedance spectroscopy results indicated that the incorporation of CeO 2 @ND particles significantly enhanced the polarization resistance and the protection efficiency of the fabricated silane-CeO 2 @ND hybrid coating was 98.3 %. Additionally, the protection efficiency of the coating slightly decreased to 98.2 % after 25 days of corrosion. Moreover, the scratch test indicated an excellent self-healing capability of silane-CeO 2 @ND nanocomposite. The outstanding self-repairing property of the coating was depended on the synergistic effects of inhibitive CeO 2 nanocontainers and the loaded ND inhibitor. • Superhydrophobic silane-CeO 2 @ND composite coating was constructed on aluminum alloy surface. • CeO 2 showed a high 1,5-naphthalenediol loading capacity of over 22 %. • The composite coating exhibited good anti-corrosion performance. • The composite coating presented excellent self-healing capability. [ABSTRACT FROM AUTHOR]

The surface oxide film has adverse effect on the brazing of aluminum alloy. In this work, the novel method of surface activation was proposed to remove the surface oxide film of aluminum alloy and promote the atomic diffusion, which improved the microstructure and mechanical properties of brazed joints. Through surface activation process, the surface oxide film was eliminated effectively. The content of grain boundary and the surface dislocation density of the aluminum alloy were increased. The atomic diffusion in brazed joints with surface activation was observed evidently and residual oxide film was removed. The microstructure and shear strength of brazed joint were improved by surface activation, which formed the sound brazed joints. [ABSTRACT FROM AUTHOR]

Over the vast open ocean, vital nutrients for phytoplankton growth in the sunlit surface layer are largely provided through physical transport from deep waters, but some nutrients are also provided through atmospheric deposition of desert dust. The extent and magnitude of dust-mediated effects on surface ocean ecosystems have been difficult to estimate globally. In this work, we use global satellite ocean color products to demonstrate widespread responses to atmospheric dust deposition across a diverse continuum of phytoplankton nutritional conditions. The observed responses vary regionally, with some areas exhibiting substantial changes in phytoplankton biomass, whereas in other areas, the response reflects a change in physiological status or health. Climate-driven changes in atmospheric aerosols will alter the relative importance of this nutrient source. [ABSTRACT FROM AUTHOR]

Background The patatin-like phospholipase 3 ( PNPLA3) rs738409 gene polymorphism is an important genetic determinant of non-alcoholic fatty liver disease ( NAFLD). However, the associations between liver fat and metabolic traits in rs738409 G allele carriers and the allelic influence on this association have not been fully studied. Aim To investigate the influence of the PNPLA3 gene polymorphism on the association of liver fat with serum metabolic factors and carotid atherosclerosis. Methods Liver fat was measured by quantitative ultrasound in 4300 subjects in the Shanghai Changfeng community and analysed for its association with obesity and metabolic factors in individuals with the PNPLA3 CC, CG and GG genotypes. Results Non-alcoholic fatty liver disease occurred in 37.9% and 28.8% of the subjects with the GG and CC genotypes respectively ( P < 0.001). Liver fat was significantly associated with body mass index, waist circumference, serum triglycerides, high-density lipoprotein cholesterol, fasting blood glucose and insulin in the PNPLA3 rs738409 G allele carriers ( P < 0.001). Compared with the CC homozygotes, the GG homozygotes presented higher liver fat and liver fibrosis scores despite their better metabolic status (comparison of regression line slopes, P < 0.05). An increase in liver fat was accompanied by a significant increase in the average and maximum carotid intima-media thickness in subjects with the PNPLA3 CC genotype but not in those with the GG genotype. Conclusions PNPLA3 rs738409 G allele carriers were found to be more susceptible to the metabolic-related hepatic steatosis, and developed NAFLD and liver fibrosis despite presenting relatively better metabolic statuses and lower risks for carotid atherosclerosis. [ABSTRACT FROM AUTHOR]

Hydrophobic silane/reduced graphene oxide (rGO) nanocomposites were successfully constructed on an AA2024-T3 aluminum alloy surface using a facile co-electrodeposition process. The composition and morphology were characterized by ATR-FTIR, XRD, Raman spectroscopy, EDX, XPS and SEM. The results revealed that the implanted GO nanosheets were partially reduced and successfully covalently bonded with silanol groups to fabricate a more compact and denser coating. Electrochemical measurements demonstrated that the electrodeposited silane/rGO nanocomposite markedly decreased the corrosion rate of the AA2024-T3 alloy in 3.5 wt% NaCl solution. The protection efficiency was maintained over 96% after 120 h of exposure, presenting excellent chemical stability. Meanwhile, a sand paper abrasion test was performed to evaluate the mechanical robustness and the contact angle was reduced by only 4.5° after 150 abrasion cycles. The excellent anti-corrosion property and mechanical robustness, along with the feasible electrodeposition procedure, show its great potential for industrial applications. [Display omitted] • Hydrophobic silane/rGO nanocomposite was successfully co-electrodeposited on AA2024-T3 aluminum alloy surface. • GO nanosheets were partially electro-reduced and covalently bonded with silanol groups in the composite coating. • The protection efficiency of silane/rGO nanocomposites remained over 96% after 120 h of exposure in 3.5 wt% NaCl solution. • The contact angle of silane/rGO nanocomposites shows a slight reduction of 4.5° after 150 abrasion cycles. [ABSTRACT FROM AUTHOR]

Changes in sarcoplasmic and myofibrillar proteins, free amino acids, and cathepsin activities were measured to evaluate the contribution of cathepsins to the proteolysis of muscle proteins in dry-cured duck processing. Thirty-six dry-cured ducks were processed with the traditional method, and samples were collected at different stages. Sarcoplasmic and myofibrillar proteins were found to be degraded to some degree at different stages, whereas content of free amino acids increased from 43.9 to 133.97 mg/100 g during the whole process. Cathepsin B, D, and L activities decreased significantly, and the activities in the end product were 22.4, 26.2, and 40.5% of those in the raw material, respectively. Statistical analysis showed there were significant correlations among changes in proteins, free amino acids, and cathepsin activities. The results indicated that cathepsins are involved in the proteolysis of muscle proteins in dry-cured duck processing. [ABSTRACT FROM PUBLISHER]

This paper explores the behaviour of carbon fibre reinforced polymer (CFRP) strengthened reinforced concrete beams with and without end anchorage provided at the ends of CFRP strips on the tension face of the beams. A total of 12 beams were tested to failure under mono tonic and cyclic loads. The beams were originally designed as either under-reinforced or almost over-reinforced concrete beams. The present experimental results show that externally bonded CFRP strips to the tension face of the beam is an effective technique for repair and retrofit of reinforced concrete beams under various loads. This study also shows that ductility of CFRP strengthened beam, in particular for a shorter beam, is adequate if the beam is properly designed and the CFRP strips are properly anchored. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to assess the efficacy of traction device-assisted endoscopic submucosal dissection (ESD) of the rectum and the distal segment of sigmoid colon using grasping forceps. Methods: A total of 43 patients scheduled for colonic ESD at our institution were enrolled between January 2013 and June 2017. The patients were randomly allocated to receive conventional ESD (group A) or traction device-assisted ESD (group B). The procedure time, complication rate, and en-block resection rate in the two groups were compared. Results: A total of 41 patients completed the study. The procedure time, complication rate and en-block resection rate were, respectively, 104.1 ± 34.7 min, 15%, 90% in the routine group (group A) and 84.7 ± 23.5 min, 9.5%, 90.5% in traction device-assisted ESD (group B). The procedure time in group B was significantly less than that in group A (F = 4.442, p < 0.05). Conclusions: Traction device-assisted ESD using grasping forceps is safe and effective in distal colon ESD. [ABSTRACT FROM AUTHOR]

Interfacial microstructure and mechanical properties of Ti–6Al–4 V/C f /β–spodumene composites joints brazed by Ag–Cu eutectic brazing filler were investigated. The effects of brazing temperature and holding time on the interfacial microstructure and mechanical properties of Ti–6Al–4 V/C f /β–spodumene composites joints were studied. The result indicated that the typical interfacial microstructure of the joint was Ti–6Al–4 V/Ti 2 Cu + α-Ti (s,s)/Ti 2 Cu/TiCu/Ag (s,s)/Cu (s,s)/Ti 2 Cu 3 /TiSi 2 + TiC/C f /β–spodumene composites. The thickness of the diffusion layer, Ti 2 Cu 3 layer, and reaction layer on the interface of C f /β–spodumene composites increased with the brazing temperature or holding time increasing, meanwhile, the thickness of Ti–Cu layers decreased. The diffusion of Ti in brazing seam, which was significantly determined by the brazing temperature and holding time, was a decisive factor on the interfacial microstructure and mechanical properties of brazed joints. The optimal shear strength of joint brazed at 880 °C for 10 min was 33.5 MPa. Further raising the brazing temperature or extending the holding time would reduce the shear strength of joints. Brazing specimens brazed at 880 °C and 910 °C for 10 min broke in form of cleavage fracture after shearing test. Moreover, the formation of excessive thickness of TiSi 2 + TiC layer or Ti 3 Cu 4 reaction layer was harmful to the mechanical property of the joint. [ABSTRACT FROM AUTHOR]

Epithelial-mesenchymal transition (EMT) induced by transforming growth factor-β (TGF-β) is implicated in hepatocarcinogenesis and hepatocellular carcinoma (HCC) metastasis. HAb18G/CD147, which belongs to the CD147 family, is an HCC-associated antigen that has a crucial role in tumor invasion and metastasis. The goal of this study was to investigate the role of HAb18G/CD147 during EMT in hepatocarcinogenesis. Human normal hepatic cell lines QZG and L02, primary mouse hepatocytes and nude mouse models were used to determine the role of HAb18G/CD147 in EMT, and the involvement of the TGF-β-driven pathway. A dual-luciferase reporter assay and ChIP were used to investigate the transcriptional regulation of the CD147 gene. Samples from patients with liver disease were assessed to determine the relationship between HAb18G/CD147 and typical markers for EMT. Our results show that upregulation of HAb18G/CD147 is induced by TGF-β coupled with downregulation of E-cadherin and upregulation of N-cadherin and vimentin. The expression of HAb18G/CD147 is controlled by the cell survival PI3K/Akt/GSK3β signaling pathway, and is directly regulated by the transcription factor Slug. Transfection of CD147 also induces an elevated expression of TGF-β. CD147-transfected hepatocytes have mesenchymal phenotypes that accelerate tumor formation and tumor metastasis in vivo. Immunohistochemistry analysis shows a negative correlation between HAb18G/CD147 and E-cadherin expression (rs=−0.3622, P=0.0105), and a positive correlation between HAb18G/CD147 and Slug expression (rs=0.3064, P=0.0323) in human HCC tissues. Our study uncovers a novel role of HAb18G/CD147 in mediating EMT in the process of HCC progression and showed that CD147 is a Slug target gene in the signaling cascade TGF-β→PI3K/Akt→GSK3β→Snail→Slug→CD147. Our results suggest that CD147 may be a potential target for the treatment and prevention of HCC. [ABSTRACT FROM AUTHOR]

The title compound is analyzed by X-ray diffraction. ONIOM(B3LYP/6-31G( d,p):PM3) is used to investigate the optimized calculation and the frequency analysis of the molecule, in which the PM3 method was used for carbon and hydrogen atoms of the benzene ring and the B3LYP/6-31G( d,p) method was used for the other parts. Energy changes in the molecule are numerically investigated by the flexible scan at PM3 level. The nature of intramolecular interactions that stabilize the structure in vacuo and solid is studied. The results reveal that the molecule is flexible and molecular conformations can easily be mutually transformed through very small potential barriers. [ABSTRACT FROM AUTHOR]

Nanostructured alumina-titania composite powders which are microsized particles composed of nanosized grains were prepared from nano alumina and titania powders with nanodopants (zirconia and ceria) by ball milling, spray drying and heat treating. Then, the as prepared nanostructured composite powders were consolidated into ultrafine grained alumina-titania bulk ceramic composites through powder compacting and pressure less sintering. The addition of nanodopants leads to a finer grain size in the ceramic and improves the densification of bulk ceramic composite. The active mechanisms of nanodopants were discussed in detail. [ABSTRACT FROM AUTHOR]

This retrospective study aimed to evaluate the risk factors for bowel resection and outcome in patients with incarcerated groin hernias. The records of all adult patients who had undergone emergency hernia repair for incarcerated groin hernia from January 1999 to June 2009 were analyzed. One hundred and eighty-two patients with incarcerated groin hernias were included in this study. Bowel resection was required in 28 patients (15.4%). One hundred and twenty-six patients (69.2%) were covered by various types of health insurance. Twenty-six patients (14.3%) were hospitalized for mechanical bowel obstruction or had obvious symptoms of simultaneous bowel obstruction. Obvious peritonitis was found in seven patients (3.8%). A logistic regression model identified three independent risk factors for bowel resection: lack of health insurance (odds ratio [OR], 5, P = 0.005), obvious peritonitis (OR, 11.52, P = 0.019), and femoral hernia (OR, 8.31, P < 0.001). Postoperative complications (standardized coefficient [SC] = 0.478, P < 0.001), presentation of bowel obstruction on admission (SC = 0.169, P = 0.017), and having health insurance (SC = 0.153, P = 0.030) were associated with prolonged length of stay. No factors were found to be directly associated with morbidity or mortality. Risk for intestinal resection in emergency groin hernia repair is higher in patients with femoral hernia, obvious peritonitis, or those with no health insurance. Surgeons should pay more attention to these patients and initiate emergency surgery without delay. [ABSTRACT FROM AUTHOR]

Abstract: The influence of C, N, O, Mg, Si and co-implants (Mg+Si) ions implantation with fluences in the wide range 1013–1017 cm−2 on the yellow luminescence (YL) properties of wurtzite GaN has been studied by photoluminescence (PL) spectroscopy. Two types of n-type GaN samples grown by metal-organic chemical vapor deposition method (MOCVD) and labeled as No-1 and No-2 were studied. In their as-grown states, No-1 samples had strong YL, while No-2 samples had weak YL. Results of the frontside and backside PL measurements in one of the as-grown GaN epifilms are also presented. Comparing the intensity of YL between frontside and backside PL spectra, the backside PL spectrum shows the more intense YL intensity. This implies that most of the intrinsic defects giving rise to YL exist mainly near the interface between the epilayer and buffer layer. Our experimental results show that the intensity ratio of YL to near-band-edge UV emission (I YL/I UV) decreases gradually by increasing the C implantation fluence from 1013 to 1016 cm−2 for No-1 samples after annealing at 900°C. When the fluence is 1017 cm−2, a distinct change of the I YL/I UV is observed, which is strongly increased after annealing. For No-2 samples, after annealing the I YL/I UV decreases gradually with increase in the C implantation fluence from 1013 to 1015 cm−2. The I YL/I UV is gradually increased with increasing C fluence from 1016 to 1017 cm−2 after annealing, while I YL/I UV for other ions-implanted GaN samples decreases monotonically with increase in the ions implantation fluences from 1013 to 1017 cm−2 for both No-1 samples and No-2 samples. It is noted that for annealed C-implanted No-2 samples I YL/I UV is much higher than that of the as-grown one and other ion-implanted ones. In addition, I YL/I UV for the Mg, Si, and co-implants (Mg+Si) implanted No-2 samples with a fluence of 1013 cm−2 after being annealed at 900°C is higher than that of the as-grown one. Based on our experimental data and literature results reported previously, the origins of the YL band have been discussed. [Copyright &y& Elsevier]

High-risk drinking on game day represents a unique public health challenge. OBJECTIVE: The authors examined the drinking behavior of college football fans and assessed the support for related interventions. PARTICIPANTS: The authors randomly selected 762 football fans, including college students, alumni, and other college football fans, to complete an anonymous online game-day survey. METHODS: The authors collected data on participants' drinking behaviors and support for specific game-day interventions. RESULTS: Analysis revealed that, overall, fans drank significantly more on game day than they did the last time they partied or socialized. Nondrinkers were the most supportive of game-day interventions, followed by moderate drinkers, whereas heavy drinkers offered the least support. CONCLUSIONS: With the exception of limiting tailgating hours on game day, fans support game-day interventions, including alcohol-free alternatives, designating tailgating areas where open containers are permitted, and increasing law enforcement efforts. [ABSTRACT FROM AUTHOR]

We present in this paper a highly stable and efficient KTP-based intracavity optical parametric oscillator with a diode-end-pumped Nd:YVO4/Cr:YAG passively Q-switched laser. At the incident diode pump power of 4 W, the signal (1.57 μm) and idler (3.29 μm) average output powers up to 580 and 100 mW, respectively, have been achieved. The corresponding conversion efficiency from the input diode pump power to the output signal power is 14.5%, while that to the total OPO output (signal+idler) reaches 17%. To the best of our knowledge, these are the highest conversion efficiencies reported to date. After more than four hours of investigation, the OPO power stability better than 2% has been obtained. In addition, efficient cavity dumping of the IOPO has inevitably led to the short pulse duration (1.6 ns) and high peak power output (8.3 kW) at the signal wave. Additionally, the amplitude and repetition rate fluctuations of the signal pulses are well within 5%. [ABSTRACT FROM AUTHOR]